Extended Data Fig. 11: Domain wall formation in different heterostructures.
From: In-plane charged domain walls with memristive behaviour in a ferroelectric film
a, The magnified STEM image of La0.7Sr0.3MnO3/BiFeO3/La0.7Sr0.3MnO3 (LSMO/BFO/LSMO) structure. b–c, The atomic-scale HAADF-STEM images of LSMO/BFO/LSMO film at 0 V and 5 V, respectively. The direction of polarization is marked by red and blue arrow. Domain wall is marked by dashed red line. Interfaces are indicated by dashed white lines. Scale bars, 1 nm. BFO shows uniform polarization at initial state. After applying voltage of 5 volt, a tail-to-tail in-plane charged domain wall is found. d, The magnified STEM image of SRO/BFO/SRO structure with thick SRO electrodes. The thickness of SRO electrode is more than 14 nm. e-f, Atomic-scale HAADF-STEM images of SRO/BFO/SRO film at 0 V and 5 V, respectively. Scale bars, 2 nm. A tail-to-tail in-plane charged domain wall is still formed when SRO electrodes become thicker. g, The magnified STEM image of SrRuO3/BaTiO3/SrRuO3 (SRO/BTO/SRO) structure. h-i, Atomic-scale HAADF-STEM images of SRO/BTO/SRO film at 0 V and 5 V, respectively. Scale bars, 2 nm. BTO shows uniform polarization at initial state. After applying voltage of 5 volt, a head-to-head in-plane charged domain wall is found. j, The magnified STEM image of SrTiO3/BiFeO3/SrTiO3 (STO/BFO/STO) structure. k-l, Atomic-scale HAADF-STEM images of STO/BFO/STO film at 0 V and 10 V, respectively. Interfaces of STO/BFO are indicated by dashed white lines. Scale bars, 1 nm. BFO is switched without charged domain wall after applying voltage of 10 volt. Without conducting electrodes such as SRO and LSMO in film, BFO switches from the uniform polarization to the opposite without forming charged domain wall.
